Radiation computed tomographic imaging apparatus and radiation detector for use therein

Abstract

An apparatus for reducing the influence by scatter rays and improving image quality of a tomographic image. The apparatus includes an X-ray detector and a calculation / control apparatus for generating tomographic image data for a tomographic image of the subject based on the projection data. The X-ray detector includes a plurality of detector channels eh for detecting the radiation, extending in a two-dimensional manner in two arrangement directions, i.e., in channel and column directions, the channel direction being contained in a plane of rotation of the X-ray source, the column direction being orthogonal to the channel direction and aligned along the axis of rotation; and collimators for confining an angle at which X-rays impinge upon the detector channels, provided at borders between the detector channels adjoining in the column direction.

Description

BACKGROUND OF THE INVENTION [0001] The present invention relates to a radiation computed tomographic imaging apparatus such as an X-ray CT (computed tomography) apparatus. More particularly, the present invention relates to a radiation computed tomography apparatus capable of acquiring volume data, such as a VCT (volume CT) apparatus or a multi-row CT apparatus, and a radiation detector for use in such an apparatus. [0002] Known X-ray CT apparatuses include, for example, one that acquires projection data for a subject by an X-ray detector having a plurality of X-ray detector channels arranged in a two-dimensional manner. The plurality of X-ray detector channels are positioned to have their width in a direction along a predefined axis with respect to the subject. Since X-ray detector channel rows are formed over a certain width in the axis direction, the X-ray detector having X-ray detector channels arranged in a two-dimensional manner is generally referred to as a multi-row detector...

AI Technical Summary

Benefits of technology

[0012] It is therefore an object of the present invention to provide a radiation computed tomographic imaging apparatus capable of more effectively reducing the influence by scatter rays, and improving image quality of a tomographic image.

[0013] It is another object of the present invention to provide a radiation detector for use in a radiation computed tomographic imaging apparatus, capable of more effectively reducing the influence by scatter rays, and improving image quality of a tomographic image.

[0019] According to the present invention, the influence by scatter rays is more effectively reduced, and image quality of a tomographic image can be improved.

Problems solved by technology

Therefore, the scatter rays cause generation of artifacts, and image quality of the tomographic image may be degraded.

The increase in the width of the X-ray fan beam causes X-rays to impinge upon more divergent positions in the subject, thus increasing the probability of generation of scatter rays.

It is therefore difficult for a collimator merely provided at each X-ray detector channel in the channel direction, as in the X-ray CT apparatus described in Patent Document 1, to effectively prevent scatter rays from impinging upon the detecting surface.

Consequently, image quality is more likely degraded.

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